into the southern half of the DMZ. From 13–16 May, 1/9 Marines cleared Route 561 from Cam Lo to Con Thien fought a well-entrenched PAVN force south of the base. The PAVN subsequently withdrew into the DMZ. Operations Hickory/Lam Son 54/Beau Charger III MAF proceeded to plan a series of combined operations with ARVN forces that occurred from 18 to 26 May. Under Operation Hickory 3rd Marine Regiment advanced to the Bến Hải River. Under Operation Lam Son 54 the ARVN 1st Division advanced parallel to the 3rd Marines along Highway 1 while the amphibious Special Landing Force Alpha secured the coastline south of the Bến Hải River under Operation Beau Charger and Special Landing Force Bravo linked up with 3rd Marines under Operation Belt Tight. Once at the Bến Hải River, the forces swept south on a broad front to Route 9. From 19 to 27 May, when Lam Son 54 ended, the ARVN were in constant contact with the PAVN. The ARVN suffered 22 killed and 122 wounded, while claiming the PAVN suffered 342 killed and 30 captured. The amphibious element of Operation Beau Charger met no opposition while the heliborne assault dropped into a hot LZ. Only one platoon was landed and it remained isolated until rescued several hours later. Beau Charger continued until 26 May with minimal contact. 85 PAVN were claimed to have been killed. In Operation Hickory, the 2nd Battalion, 26th Marines and 2nd Battalion, 9th Marines advanced north from Con Thien on the morning of 18 May to press any PAVN against a blocking force from the 3rd Battalion, 4th Marines 3/4th Marines landed by helicopters on the Bến Hải River. At 10:00, 2/26th Marines made contact with 2 PAVN Battalions in bunkers and trenches. The 2/9the Marines joined 2/26th and fought a running battle until nightfall. Five Marines were killed and 142 were wounded, while 31 PAVN were killed. That night 75 radar-controlled airstrikes were called in on the bunker complex. At 07:00 on 19 May after 2 hours of artillery preparation (in which short rounds killed 3 Marines), the 2/26the Marines proceeded to attack the bunker complex, overrunning it by 10:30 and claiming to have killed 34 PAVN. At 13:30 2/9th Marines met heavy automatic weapons and mortar fire and an M48 tank moved up to silence the PAVN positions with canister fire. 2 M48s were later knocked out by RPG-2